ZeniMax announces having shipped 10 million copies of The Elder Scrolls V: Skyrim, and quotes Valve's Jason Holtman calling the RPG sequel "the fastest selling title in Steam's history." Here are the relevant quotes:

December 15, 2011 (Rockville, MD) – ZeniMax® Media Inc. today announced that 10 million units of Bethesda Softworks’® The Elder Scrolls V: Skyrim have been shipped for the Xbox 360® video game entertainment system from Microsoft, PlayStation®3 computer entertainment system, and PC, representing approximately $650 million in retail sales since its release on November 11. The PC version of Skyrim in North America outsold all other PC games by a factor of over three to one in the month of its release. Large retail reorders across all platforms and record-breaking digital sales reflect the ongoing global demand by consumers excited to explore this extraordinary fantasy epic.
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“Skyrim is the fastest selling title in Steam's history” said Jason Holtman, Director of Business Development at Valve Corporation. “Bethesda’s commitment to and understanding of the PC as a gaming platform shows in the great review scores, spectacular launch, and continued high player numbers that Skyrim has received. We are delighted that Bethesda chose to use Steamworks to support Skyrim both at retail and digitally.”